Abstract: An apparatus (100), and method, for calibrating gain in satellite uplink receiver electronics includes an uplink receiver, a measurement processor, and an attenuator (106). The measurement processor receives the uplink signal from the uplink receiver and includes circuitry to sample (118) the uplink signals during a blanking interval and outputs a gain calibration signal. The sampling circuitry (118) may sample uplink signals periodically or responsive to extreme changes in conditions, and may sample the uplink signal multiple times during a blanking interval to output a multiple measurement sample. The measurement processor may include averaging circuitry (124) to produce a sample average. The method and apparatus (200) may both be used with TDMA systems.